1. Field of the Invention
This invention relates to detergent compositions in the form of tablets, particularly for use in dishwashing, laundry washing and water softening and use applications thereof, and, more particularly, to a composite disintegration blend of defined amounts of a water-soluble salt, and crosslinked polyvinylpyrrolidone, having a disintegration rate of at least 40 g/min.
2. Description of the Prior Art
Tablets have the advantage that they do not require the user to measure out a volume of powder or liquid. Instead, one or several tablets provide an appropriate quantity of composition for washing a single load in, for example, a dishwashing machine. Tablets thus are easier for the consumer to handle and dispense.
Detergent compositions in tablet form have been described in a number of documents and are sold commercially.
Such tablets generally are made by compressing or compacting a quantity of detergent composition in particulate form. It is desirable that tablets should have adequate mechanical strength when dry before use, yet disintegrate and disperse/dissolve quickly when added to wash water. However, it is often difficult to achieve both properties simultaneously. As more pressure is applied when a tablet is compacted, the tablet density and strength rises (a hard tablet), but there is also a reduction in the speed of disintegration/dissolution when the tablet comes into contact with wash water at the time of use. Organic detergent serves as a binder, but a typical quantity of such detergent can also retard disintegration and dissolution of a tablet.
The prior art has described the numerous difficulties in providing suitable tablets of detergent compositions, including EPA 466485; WO 00/32741; EPA 711827; EPA 838519; WO 99/36493; WO 98/55583; GB 911204; U.S. Pat. No. 3,953,350; JP 60-015500A; EP-A-711827; WO 96/28530; EP 1070741; and EP 1036839.